French patents FR-2,446,180 and FR-2,550,123 describe how to produce monoblock composite connecting rods whose running portion and end portions are entirely made up of preimpregnated fibers placed on a suitable mandrel which is then placed in a mould whose internal wall fits the shape of the connecting rod to be embodied for the purposes of polymerization.
In FR-2,446,180, the fibers appear in the shape of a fabric wound several turns or "folds" on a deformable mandrel which is then flattened at the two ends.
This technique, apart from the fact that it prohibits embodying heads of a strap connecting rod, does not make it possible to deliberately modulate the local characteristics of the composite material along the connecting rod since this method begins using pre-existing fabrics which are simply plated on the mandrel. In addition, this technique does not really involve genuine monoblock connecting rods as the mandrel remains inside the connecting rods.
In FR-2,550,123, the fibers are placed unidirectionally in the longitudinal axis of the connecting rod on an expansible mandrel which shall next be "inflated" to fit the shape of the mould.
This unidirectional placing required by the expanding of the coated mandrel does not make it possible to longitudinally vary on the connecting rod the fiber placing characteristics and solely concerns resistance to longitudinal stresses.